<!DOCTYPE html>
<html lang="en">

<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>Document</title>
	<script type="text/javascript">

		var str = prompt("请输出任意的内容:");

		//var arr = str.split("");

		//arr.reverse();

		//str = arr.join("");

		str = str.split("").reverse().join("");

		alert(str);

	</script>
</head>

<body>

</body>

</html>